×

Test device and method for colored particle immunoassay

DC
  • US 5,989,921 A
  • Filed: 07/02/1997
  • Issued: 11/23/1999
  • Est. Priority Date: 06/27/1988
  • Status: Expired due to Term
First Claim
Patent Images

1. A test device for determining the presence of a ligand in a liquid sample, the device comprising:

  • a casing defining an inlet and at least one window for viewing through a wall of said casing,a test strip disposed within said casing comprising a sorbent material which defines a flow path for transporting the liquid sample therealong from said inlet to a test site and a control site, and,disposed upstream of said test site and said control site, a conjugate comprising a specific binder for the ligand and a colored particulate material,said test site comprising an immobilized first binding protein which binds specifically to the ligand, if the ligand is present in the liquid sample, andsaid control site comprising an immobilized binder which binds said conjugate,wherein said inlet, said test site, and said control site are in lateral flow fluid communication along said flow path, such that after a liquid sample suspected to contain the ligand is applied to said inlet,said conjugate moves along said flow path and binds to said immobilized binder of said control site to produce a color visible to the unaided eye through said at least one window indicative of a valid test result, and,if the ligand is present in the liquid sample, a specific binding reaction product comprising the ligand and said conjugate binds to said immobilized first binding protein of said test site to produce a color visible to the unaided eye through said at least one window indicative of the presence of the ligand in the sample.

View all claims
  • 3 Assignments
Timeline View
Assignment View
    ×
    ×